This invention relates to a water jet propulsion device and more particularly to an improved power operated trim adjustment mechanism for a watercraft.
It is well known that the trim of a watercraft is very important in the performance of its propulsion unit. This is particularly true with respect to jet propelled watercraft where the jet propulsion unit discharges water through a discharge nozzle for propulsion of the watercraft. Frequently, the discharge nozzle is also steerable about a vertically extending axis for steering of the watercraft.
The efficiency of the jet propulsion unit will depend to a large extent to the angle of discharge of the water relative to the horizon or horizontal plane. However, as the loading on the watercraft varies, the trim of the watercraft can change and this can adversely affect the efficiency of the propulsion unit.
At times, it may be possible to provide an arrangement wherein the discharge nozzle of the jet propulsion unit is pivotal about a horizontally disposed axis to change the trim angle in response to loading conditions in the watercraft and other factors. In some instances, rather than moving the jet propulsion unit discharge nozzle, a separate trim plate may be employed for the same or a similar purpose. The previously proposed systems have, however, required manual control and hence are not completely satisfactory.
It is, therefore, a principal object to this invention to provide an improved trim adjusting mechanism for a watercraft.
It is a further object to this invention to provide a improved trim adjusting apparatus for a jet propelled watercraft.
It is a further object to this invention to provide a trim adjustment apparatus for a watercraft that is power controlled so as to permit ease of operation and trim adjustment even when traveling at high rates of speed.